Scientists Identify Gene Variant Linked To Swine Flu In Han Chinese

AsianScientist (Feb. 4, 2013) - Researchers at Oxford University and Beijing Capital Medical University have found a genetic variant which explains why Chinese populations may be more vulnerable to the H1N1 form of flu, commonly known as swine flu.

The findings, published last week in Nature Communications, could help identify those at high risk of severe infection and help prioritize those in highest need of treatment.

Led by Dr. Tao Dong at the MRC Human Immunology Unit, Oxford University, the study showed that having this variant in your genetic make-up could increase your chances of severe infection by six times.

The variation rs12252-C is occasionally found in Caucasian populations (in around 1 in 3,000 people) and was previously shown to be associated with more severe influenza. The researchers focused on this variation as it is 100 times more common in Han Chinese, the predominant ethnic group in China.

"Understanding why some people may be worse affected than others is crucial in improving our ability to manage flu epidemics and to prevent people dying from the virus. Previous studies had shown genetic variant was associated with severe influenza infection in Europeans, but this variant is extremely rare in Europeans. We became interested in this because we noticed it is 100 times more common in China," said Tao.

Results of the study showed that the rs12252-C variation was present in 69 percent of Chinese patients with severe pandemic (swine) influenza in 2009 compared with 25 percent who only had a mild version of the infection.

"The apparent effect of this gene variant on the severity of influenza is of great interest. It remains to be seen how this gene affects the whole picture of influenza in China and South East Asia but it might help explain why new influenza viruses often first appear in this region of the world," said Professor Andrew McMichael at the MRC Human Immunology Unit, Oxford University, a co-author on the study.